Time to give it a rest, Liam: The novelty of Neeson as an action hero has clearly worn off, no more so than in “Taken 2.”

In the surprise 2009 box-office smash “Taken,’’ Liam Neeson played a retired CIA operative who rescues his teenage daughter from Albanian white slavers and then goes all Mel Gibson on the culprits.

In the inevitable — if far less exciting and vastly sillier — sequel, Neeson quickly loses the daughter (Maggie Grace, clearly pushing 30 in real life) again on a trip to Istanbul, where life is cheap and the movie production subsidies are generous.

A bunch of Albanians (led by Rade Serbedzija) want revenge on Neeson for killing and torturing their relatives in the first film.

At various points they also kidnap Neeson and Neeson’s estranged wife (Famke Janssen, whose double spends most of the movie with a sack on her head).

But these truly inept killers never manage to hold onto the entire clan at the same time.

In the interest of advancing the plot, the idiotic bad guys conveniently ignore barking dogs and other warning signs that Neeson or the daughter are approaching, as well as the miniature cellphone Neeson uses to repeatedly communicate with the daughter while in captivity.

“Act casually,’’ he advises her in a truly hilarious sequence — sending the young woman out to toss grenades off Turkish rooftops so he can use the sound of the explosions to help direct her to where he’s being held.

There are other indications that screenwriters Robert Mark Kamen (“The Karate Kid’’) and Luc Besson (who also produced this one) didn’t necessarily want the audience to take “Taken 2’’ as seriously as, say, “Taken.’’

Like when the daughter — who has failed her driving test back in California twice — takes the wheel in a high-speed chase through narrow twisting streets to elude the killers, while dad is directing her to ignore scurrying pedestrians.

This sort of approach has diminishing returns in an alleged thriller: There doesn’t seem to be a whole lot at stake in a movie where you can crash your way through the armed barricades at the American embassy with a stolen taxicab and survive without a scratch.

Four years ago, there was novelty value in seeing an actor with Neeson’s gravitas turning mad action hero. But Neeson’s done it several times since, with diminishing returns, in other paycheck jobs.

Olivier Megaton, the wonderfully named Besson protégé who directed, stages action sequences clumsily and edits them so frantically it looks like the whole movie was run through a Cuisinart.

When Neeson engages in bare-knuckle fisticuffs at the climax of the cartoonish “Taken 2,’’ I honestly couldn’t figure out if the 60-year-old actor was actually present at all except for the close-ups.